A lot of people actually aren’t okay that cars kill so many people, on top of the other enormous externalities. No single person woke up one day and did a cost-benefit analysis on private automobile travel (and if they had, they might’ve come to the conclusion that it’s dangerous and bad for the environment). But we shouldn’t assume that just because the world is the way it is that it was the result of careful reasoning by all of society and not individual decisions of decades, many of which were made in bad faith or for nefarious purposes.

I.e. just because we use coal doesn’t mean society is okay with it.